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941.
建立深圳市机动车氮氧化物排放因子初探   总被引:3,自引:0,他引:3  
针对国内机动车排放因子研究处于起步阶段的实际情况,因地制宜地确定了深圳市当地的机动车氮氧化物排放因子研究技术路线,通过大量的调研、实测建立深圳市道路和联片建成区机动车氮氧化物排放因子,为深圳市机动车排气污染研究和控制提供了参数.  相似文献   
942.
电热原子吸收悬浊液进样法测定环境样品中的锰   总被引:4,自引:0,他引:4  
本文利用生物胶作为稳定剂,把难溶环境固体样品制备成悬浊液,直接进样测定煤飞灰中的锰,并且利用塞曼背景扣除法,得到了准确的结果。文章找出了日立18080石墨炉原子吸收光谱仪的测定适用条件,原子化温度,生物胶最佳用量范围,比较了不同信号采集方式、不同石墨炉类型造成的差异,并分析了酸度、搅拌、粒度对测定结果的影响。  相似文献   
943.
长江源区浮游生物调查初报   总被引:5,自引:0,他引:5  
本文简要报告了长江源区包括长江正源沱沱河等三条河流浮游生物的初步调查结果。  相似文献   
944.
深圳市地表水水质自动监测子站安装了HACH AMTAX inter2、科泽K301、WTW Trescon UN和瑞士万通ALERTCOLORIMETER ADI 2004氨氮自动分析仪。以潮汐河流深圳河为例,从仪器测量原理、分析方法、测量过程、分析能力、对海水适应性等方面分析比较四种氨氮自动分析仪与实验室方法之间的异同。  相似文献   
945.
于2015年2月1~7日利用多波束测深系统对长江口横沙通道河槽进行走航测量,结合人类活动强干扰下的海图水深数据及河槽表层沉积物资料分析近期长江河口横沙通道河槽冲淤变化与微地貌特征,探讨河槽冲淤演变和床面微地貌之间的相关性以及河口河槽冲淤演变过程和微地貌特征对人类活动的响应。结果显示:近年来横沙通道河槽持续受到冲刷,2002~2013年泥沙净冲刷量为0.86 × 108m3,平均每年冲刷0.08 × 108m3,其原因可能与三峡蓄水工程、北槽深水航道治理工程和北港青草沙水库工程的实施有关。而横沙通道的河床冲刷对圆圆沙航槽和北槽航道的泥沙回淤具有一定的贡献;其底床上除发育平滑床底外,还广泛发育凹坑和冲刷痕等侵蚀性微地貌,且河槽受到冲刷导致底沙推移质运动增强,促进了沙波微地貌的发育。  相似文献   
946.
The interaction between human and land in estuarine–coastal areas has become a focus of the global change research. Since the sixteenth century, the Old Huanghe River delta has experienced rapid accretion, the formation of rich ecological resources and diverse land use pattern changes; such information, in combination with a large number of historical documents, provides a unique research area for revealing the processes for ecosystem–human changes. We use historical documents and adopt multidisciplinary methods, to identify the relationship between ecosystem changes and human activities, on the basis of spatial and temporal analysis, for in the Old Huanghe River delta region. The results indicate that, in the sixteenth to nineteenth centuries, the long-term monopolistic development pattern under the government leadership, which occupied large quantities of ecological resources, controlled the coastal salt industry and marsh land exploitation. However, along with the delta ecosystem change and population growth, the development pattern became gradually unsustainable, i.e., the salt industry migrated toward the north, while the farming activities migrated toward the south with enhanced intensity of marsh reclamation. The government monopoly collapsed in the late nineteenth century, which enlarged the independent development space for the local residents, which, to a large extent, improved the land-use efficiency and reduced the population pressure.  相似文献   
947.
<正>火灾条件下电缆燃烧烟气的毒性分析对于电缆火灾安全研究非常重要。为了研究典型电缆燃烧烟气的组分及毒性大小定量,通过搭建试验装置并进行实验研究。对采集的实验数据采用FED模型进行了烟气的毒性评价,并进一步采用因子分析法对组分烟气数据进行分析。分析结果表明,基于因子分析法的烟气毒性评价方法与FED模型分析结果趋于一致,但此方法可以揭示出更多有用信息用以指导电缆火灾危险性评价。研究为电缆燃烧烟气的毒性效应评价提出了一种新的思路。  相似文献   
948.
Acidification of mine wastes can lead to a series of environmental problems, such as acid drainage, heavy metal mobilization, and ecosystem degradation. Prediction of acid-forming potential is one of the key steps in management of sulfide-bearing mine wastes. In this paper, the acid-forming potential of 180 mine waste samples collected from 17 mine sites in China were studied using a net acid generation (NAG) method. The samples contained different contents of total sulfur (ranging from 0.6 to 200 g kg(-1)), pyritic sulfur (ranging from 0 to 100 g kg(-1)), and acid neutralization capacity (ANC, ranging from -41 to 274 kg H2SO4 t(-1)). Samples with high acid-forming potential are generally due to their high sulfur content or low acid neutralization capacity. After the samples were oxidized by H2O2, the amounts of acid generation and the final NAG pH were measured. Results indicated that the final NAG pH gave a well-defined demarcation between acid-forming and non-acid-forming materials. Samples with final NAG pH >or= 5 could be classified as non-acid-forming materials, while those with NAG pH 2.5, but < 5, had low risk of being acid-forming. The confirmation of cut-off NAG pH will be used as a rapid and cost-effective operational monitoring tool for the in-pit prediction of acid-forming potential of mine wastes and classification of waste types.  相似文献   
949.
950.
This study investigates six water quality monitoring stations in the watershed of the Feitsui Reservoir. It uses nine parameters of water quality collected in an interval of two and half years for factor analyses, which was first conducted to determine four types of factors, respectively, those for organic pollution, eutrophication, seasonal influence, and sediment pollution. The analysis results effectively help to determine water quality in the watershed of the reservoir. The authors reutilize analysis of moment structures (AMOS) to acquire further results in order to confirm the goodness of fit of the previous factor analysis model. During the confirmation, we examine the hypothesized orthogonal results as well as utilize oblique rotation to explore the goodness of fit of the reflective indicators of the orthogonal rotation. As shown in the algorithm results, as long as the covariance curve is included in the four factors, no related issues are detected in the goodness of fit of reflective indicators and interior and external quality is reported with excellence. The orthogonal model, thus, stands. Additionally, when the analysis of structural equation modeling (SEM) is conducted, sample data mismatches the hypotheses of multivariate normality. Therefore, this study adopts the generalized least square (GLS) for an algorithm. Research results of this study have been submitted to the reservoir management authorities in Taiwan for the improvement of statistical application and strategic evaluation of water quality monitoring data in order to strengthen the managerial effectiveness of water quality in watersheds.  相似文献   
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